As long as your phylactery is safe, you are immortal. Everytime you die your body turns into ashes and you appear within 1d4 days near your phylactery. This trait only works if your phylactery isn't destroyed

Your phylactery has 10 AC and 20 HP and has resistance to all non magical damage.

If your phylactery is destroyed, you must make a new phylactery made from 50gp of silver and must have all the runes inscribed which will take you 7 hours. After the phylactery is created you must kill an intelligent humanoid creature and pour it's blood onto the phylactery. The phylactery will then glow and you must then pour your blood onto the phylactery in which the process is done and a new phylactery is created.

At 10th level you can do the process above and create a second phylactery. At 20th level you can make a third phylactery.

You can put your phylacteries in multiple places and if you die you may choose which phylactery to spawn nearby to.

You gain the Chill Touch cantrip at 1st level. Additionally you can cast Ray Of Sickness as a first level spell an amount of times equal to your intelligence modifier, you regain expended uses after finishing a long rest. At 5th level you can cast animate undead twice as a third level spell and regain expended uses after a long rest. At 11th you can cast Eyebite as a 6th level spell once and regain the ability to do so after a long rest.

Intelligence is used for the spells

Spell attack = int modifier + proeficiency bonus

Spell DC = 8 + proeficiency bonus + int modifier

As an action you can cause an undead of CR level 1 and lower to roll a Wisdom saving. Failing the saving throw will force them to serve you for 1 week but if they succeed they are immune to this charm for 24 hours.

Also lesser undead (CR level 3 and lower) will not attack you unless you damage them.

Your stats are now undead and you receive damage from healing spells and healing potions. Additionally you receive health equal to the amount of poison damage you were supposed to take.

You do not age and do not need to eat, breathe, and drink.

You are also affected by all things that affect undead, such as turn undead.